#include <stdio.h>
#include <gsl/gsl_poly.h>

int main(void)
{
	int i;
	/* coefficients of P(x) = -1 + x^5 */
	double a[6] = { -1, 0, 0, 0, 0, 1 };
	double z[10];

	gsl_poly_complex_workspace* w = gsl_poly_complex_workspace_alloc(6);
	gsl_poly_complex_solve(a, 6, w, z);
	gsl_poly_complex_workspace_free(w);

	for (i = 0; i < 5; i++)
	{
		printf("z%d = %+.18f %+.18f\n",
			i, z[2 * i], z[2 * i + 1]);
	}
	return 0;
}